Automatic starting mechanism for internal combustion engines



Aug. 8, 1933. c, McNElL 1,920,996

AUTOMATIC STARTING MECHANISM FOR INTERNAL COMBUSTION ENGINES Filed July11, 1932 2 Sheets-Sheet 1 1 I {a A Z 87 Joflgnufwn AAA/\AAAA MN v vINVENTOR I mess: in

Wm M ,1 TORNEV C. l. M NEIL Aug. 8, 1933.

AUTOMATIC STARTING MECHANISM FOR INTERNAL COMBUSTION ENGINES 2Sheets-Shet 2 Filed July 11, 1932 INVENTOR 'C/zar J hLcTLeLb TTORNEYPatented Aug. 8, 1933 UNITED STATES PATENT OFFICE AUTOMATIC STARTINGMECHANISM FOR INTERNAL CODIBUSTION ENGINES York Application July 11,1932. Serial No. 621,985

11 Claims. (Cl. 290-37) This invention relates to automatic startingmechanism for internal combustion engines and more particularly to novelcontrolling mechanism for preventing undesired actuation of the startingmechanism at low engine speeds or during backward rotation of theengine.

It is an object of the present invention to provide a novel controllingdevice for starting mechanism embodying positively actuated means forpreventing operation of the starting mechanism during self-operation ofthe engine.

It is another object to provide such a device in which a plurality ofthe products of engine rotation are used to lock the starting mechanismout of operation.

It is a further object to provide such a device in which the lock-outmeans is efiective for rotation of the'engine in either direction. I

It is another object to provide such a device incorporating means fordelaying actuation of the starting mechanism until a predetermined timeafter the engine has come substantially to rest.

Another object is to provide such a (device in which said time delay isequally effective for forward and rearward rotation of the engine.

Further objects and advantages will be apparent to those skilled in thisart from the following description taken in connection with theaccompanying drawings in which:

Fig. 1 is a semi-diagrammatic illustration of a preferred embodiment ofthe invention; and

Fig. 2 is a similar view of a second embodiment of the invention.

Referring first to Fig. 1 of the drawings, there is illustrated astarting system for an internal combustion engine, not shown, comprisinga battery 1 grounded at 2 and connected by a lead 3 to anelectro-magnetic starting switch 4. The switch 4 is connected through asingle turn coil 5 and a lead 6 to a starting motor SM which is groundedat '7 to complete the starting circuit. A control circuit for thestarting switch is illustrated comprising a solenoid 8 connected by alead 9 to a manual switch 11 which may as indicated be the ignitionswitch of the engine and which is connected through an ammeter A to thebattery lead 3. The opposite end of solenoid 8 is connected by a lead 12to a fixed contact 13 which is normally engaged'by a movable contact 14mounted on a spring strip which is grounded as indicated at 16 tocomplete the control circuit.

Means. for opening the control circuit when the engine starts areprovided in the form of a magnetic plunger 17 which is arranged to bemoved downwardly into engagement with a stop 18 by means of a solenoid19 connected at one end by a lead 21 to the starting motor side of thestarting switch 4, and grounded at its other end as indicated at 22. Theplunger 17 is normally maintained in its upper position as illustratedby suitable means such as a spring 23, and is maintained in thatposition during cranking by the single turn coil 5 which is energized bythe cranking current. However, when the engine starts, the release ofthe load on the starting motor reduces the current flux through the coil5 thereby weakening said coil sufficiently so that the solenoid 19 isenabled to move the plunger 17 down against the stop 18.

When the plunger moves downwardly under the action of coil 19, a lever24 is swung there- I by to engage a weight member 25 on the end of thespring strip 15 and bend said strip backward to open contacts 14, 13.

Means are provided for retaining the plunger 17 in its retractedposition and hold contacts 13, 14 open during self-operation of theengine in the form of a coil 26 connected at one end' by a lead 27 to anengine driven generator G, and

7 source of fluid pressure operated by the engine such as the intake orexhaust manifold or an engine driven pump. As here illustrated, it isintended that the connection be made to the intake manifold or to avacuum pump whereby the diaphragm will be moved downwardly by vacuum orupwardly by pressure due to backward rotation' of the engine.

An auxiliary switch arm 32 is arranged to be operated by the diaphragm28 through a link 33 whereby motion of the diaphragm in either directionwill cause contact to be made between the switch arm 32 and one or theother of a pair of contacts 34 and 35 which are connected by a lead 36to the generator coil lead 27. The switch arm 32 is connected by a lead38 to the battery lead 9 whereby closure of this auxiliary circuitcauses energization of the generator coil 26 from the battery 1. Asuitable resistance 39 is preferably inserted in the generator lead 27between the connection of the auxiliary lead 36 thereto and thegenerator in order to insure effective energization of the generatorcoil 26 even though the engine be stationary and prevent excessivedischarge of the battery through the generator when the engine isidling.

In the operation of this embodiment of the invention, starting with theparts in the positions illustrated, closure of the ignition switch 11causes energization of the solenoid 8 to close the starting switch 4whereupon cranking of the engine takes place, the plunger 17 of thecontrol relay being maintained in its upper position by the single turncoil 5. When the engine starts, the reduction in the cranking currentweakens the coil 5 sufficiently to allow the coil 19 to move plunger 17to open the control contacts 13, 14. Meanwhile, the vacuum in the intakemanifold acting on the diaphragm 28 causes closure of the auxiliarycircuit through the contact 35 whereby the generator coil 26 isenergized from the battery 1 to retain the plunger 17 in its lowerposition.' When the generator picks up as the engine starts, itcooperates to maintain the energization of coil 26 under all operatingconditions.

In case of back-fire or backward rotation of the engine, the pressurebuilt up in the engine intake causes the diaphragm 28 to close theauxiliary circuit through the contact 34 whereby the plunger 17 is helddown during the backward rotation of the engine.

Whenthe plunger 17 is released, the lever 24 is snapped up by the actionof spring 23, whereby the weight mmber 25 is suddenly released and willcontinue to vibrate for a predetermined time thus preventing effectiveclosure of the control circuit until after the engine has had time tocome completely to rest. It will be noted that this time delay isequally eflective whether the engine has been rotating backward orforward.

In Fig. 2 there is illustrated a second embodiment of 'the invention inwhich the starting circuit is arranged substantially similar to theembodiment shown in Fig. 1, the elements thereof being similarlynumbered. In this embodiment, however, the control relay is providedwith two sets of contacts in parallel, one set 41, 42 being normallyclosed, and the other set, 43, 44, being normally open. Contact 41 ismounted on a vibrator strip 45 having a weight member 46 arranged to beactuated by a clapper type armature 47 to move said contact to openposition.

. Armature 4'7 is normally held out of engagement with weight member 46by means such as a spring 50, and is arranged to engage and move saidweight member to open contacts 41, 42 under the influence of a coil 48grounded at 51 and connected by a lead 49 to the starting motor side ofthe starting switch 4. Armature 47 is arranged to be retained in itsattracted position by means of a generator coil 52 grounded at 51 andconnected by a lead 53 to generator G.

Contact 44 is mounted on a clapper type armature 54 normally held openby a spring 55, but arranged to be closed by cranking current traversingthe single turn coil 5. The strength of spring 55 is adjustable bysuitable means such as indicated at 56 whereby cranking current willclose contacts 43, 44 but the reduction in the starting current when theengine becomes self-operative will allow the spring 55 to open saidcontacts. Contact 43 may if desired be mounted on a strip of bi-metal 57attached to an element of the starting switch 4 whereby overloading ofthe starting circuit will cause the contact 43 to be withdrawn tointerrupt the cranking operation.

In this embodiment of the invention, an, auxila iary circuit is providedfor energization of the generator coil 52 from the battery 1 comprisinga lead 58 connected to the ignition switch lead 9 and having contacts 59and 61 arranged to be engaged by a switch arm 62 which is connected by alead 63 to the generator coil lead 53. The switch arm 62 is arranged tobe operated from a piston 64 by means of a link 65, said piston beingslidable within a cylinder 66 having means for connection with anengine-operated source of fluid pressure such as the intake manifold.The switch member 62 is yieldably centered by suitable means such as aspring member 68. A resistance 69 similar to .resistance 39 ispreferably inserted in the generator lead 53.

In the operation of this embodiment of the invention, closure of theignition switch 11 completes the control circuit through the contacts41, 42, thus causing closure of the starting switch 4 and consequentenergization of the starting motor. The consequent energization of thesingle turn coil 5 causes closure of the contacts 43, 44, while theenergization of the coil 48 causes opening of contacts 41, 42. It willbe understood that contacts 43, 44 close prior to the opening ofcontacts 41, 42 inasmuch as the self-inductance of the single turn coil5 is much smaller than that of the shunt coil 48.

As soon as the engine starts, contacts 43, 44 are opened by the spring55 due to the weakening of the single turn coil 5, thus opening thecontrol circuit and causing the starting switch 4 to be opened. Theshunt coil 48 is thereby denergized, but contacts 41, 42 are maintainedopen by action of coil 52 which is energized through the auxiliarycircuit from battery 1 which circuit has been closed through the contact61 by the movement of piston 64 under the efiect of intake vacuum. Whenthe generator G picks up, it cooperates with the auxiliary circuit inmaintaining the coil 52 energized under all operating conditions.

In case of backfire, the auxiliary circuit will be energized throughcontact 59 by reason of the actuation of piston 64 by the pressure inthe intake manifold, whereby the coil 52 will be energized to maintaincontacts 41, 42 open as long as the backward rotation of the enginepersists.

When the coil 52 is deenergized, the armature 47 is released, thusreleasing the weight member 46 which vibrates for a predetermined timebefore coming to rest whereby the closure of the starting switch 4 isdelayed to allow the engine to come completely to rest as above setforth.

Although but two embodiments of the invention have been shown anddescribed in detail, it will be understood that other embodiments arepossible and that various changes may bemade in the design andarrangement of the parts without departing from the spirit of theinvention as defined in the claims appended hereto.

What is claimed is:--

1. In' an automatic starting mechanism for internal combustion engines,a starting circuit including a battery and a magnetic starting switch, acontrol circuit for said switch including a control relay, an enginedriven generator, means energized thereby for holding open said controlrelay and means responsive to self-operation of the engine forenergizing said holding means from said battery.

2. In an automatic starting mechanism for internal combustion engines, astarting circuit including a battery and a magnetic starting switch, acontrol circuit for said switch including a control relay, an enginedriven generator, means 3. In an automatic starting mechanism forinternal combustion engines, a starting circuit including a battery anda magnetic starting switch, a control circuit for said switch includinga control relay, an engine driven generator, a holding coil for saidrelay adapted to be energized by said generator, a switch for connectingsaid coil to said battery and means responsive to fluid pressuregenerated by self-operation of the engine for closing said switch.

4. In an automatic starting mechanism for internal combustion engines, astarting circuit including a battery and a magnetic starting switch,

a control circuit for said switch including a control relay, an enginedriven generator, a holding coil for said relay adapted to be energizedby said generator, a switch for connecting said coil to said battery,means responsive to fluid pressure generated by rotation of the enginein either direction for closing said switch, and means for delayingactuation of the starting mechanism for a predetermined time after thedeenergization of said holding coil.

5. In an automatic starting mechanism for internal combustion engines, astarting circuit including a battery and a magnetic starting switch, acontrol circuit therefore including a circuit making and breaking means,means for opening said making and breaking .means when the enginestarts, an engine driven generator, electromagnetic means energizedthereby for holding said making and breaking means open as long as theengine is self-operative, and means responsive to self operation' of theengine for energizing said electro-magnetic holding means from saidbattery.

6. In an automatic starting mechanism for internal combustion engines, astarting circuit including a battery and a magnetic starting switch, acontrol circuit therefor including a circuit making and break-ing means,means for opening said making and breaking means-when the engine starts,an engine driven generator,

electro-rnagnetic means energized thereby for holding said making andbreaking means open as long as the engine is self-operative and fluidpressure means responsive to rotation of the engine for connecting saidelectro-magnetic hold ing means to be energized by said battery.

7. In an automatic starting mechanism for internal combustion engines, astarting circuit including a battery and a magnetic starting switch, acontrol circuit therefor including a circuit making and breaking means,means for opening said making and breaking means when the engine starts,an engine driven generator, electro-magnetic means energized thereby forholding said making and breaking means open as long as the engine isself -operative, means including an auxiliary switch for connecting saidelectro-magnetic holding means to be energized by said battery, andfluid pressure means for closing said auxiliary switchresponsive'torotation of the engine in either direction.

8. In an automatic starting mechanism for internal combustion engines, astarting circuit including a battery and a magnetic starting switch, 'acontrol circuit therefor including circuit making and breaking meanshaving two sets of contacts in parallel, means energized by crankingcurrent for closing one of said sets ofcontacts, means energized byclosure of the starting circuit for opening the second set of contacts,and electromagnetic means responsive to a plurality of products ofself-operation of the engine for holding open said second set ofcontacts.

9. In an automatic starting mechanism for internal combustion engines, astarting circuit including a battery'and a magnetic starting switch, acontrol circuit therefor including circuit making and breaking meanshaving two sets of contacts in parallel, one set being normally open andthe other set normally closed, means energized by cranking current forclosing the normally open contacts, means energized by closure of thestarting circuit for opening the normally closed contacts, means foropening the normally open contacts when the engine starts andelectro-magnetic means responsive to a plurality of products of rotationof the engine for holding openthe normally closed contacts duringrotation of the engine in either direction.

10. In an automatic starting mechanism for internal combustion engines,a starting circuit including a battery and a magnetic starting switch, acontrol circuit therefor including circuit making and breaking meanshaving two sets of contacts in parallel, one set being normally open andthe other set normally closed, means energized by cranking current forclosing the normally open contacts, means energized by closure of thestarting circuit for opening the normally closed contacts, means foropening the normally open contacts when the engine starts, an enginedriven electro-magnetic means energized generator, thereby for holdingopen said normally closed contacts, and means responsive to rotation ofthe engine for energizing said electro-magnetic holding means from saidbattery.

1-1. In an automatic starting mechanism for internal combustion engines,a starting circuit including a battery and a magnetic starting switch, acontrol circuit therefor including circuit making and breaking meanshaving two sets of contacts in parallel, one set being normally open andthe other set normally closed, means energized by cranking current forclosing the normally open contacts, means energized by closure of thestarting circuit for opening the normally closed contacts, means foropening the normally open contacts when the engine starts, an enginedriven generator, electro-magnetic means energized thereby for holdingopen said normally closed contacts, and fluid'pressure means responsiveto rotation of the engine in either direction for connecting saidelectro-magnetic holding means to be energized by said battery.

CHARLES r. MCNEIL.

